Code:
var req = http.request(options, function(res) {
res.setEncoding('utf8');
res.on('data', function (chunk) {
var raw_data = chunk
**console.log('raw_data:', raw_data);**
}
});
This is what I got (can't copy & paste here so I put a screen shot)

You are receiving binary data.
When you log the data out you are interpreting this as text, sending it through an encoding process. My best guess is that the heart symbol is the first byte, then you have a sequence that terminates the string.
Use a simple loop to write out the data if you want to visualize it.